ECP 6 Flashcards
What are the 7 halsted principles during surgery
- Observe strict aseptic technique
- Thorough knowledge of anatomy and technique
- Control haemorrhage meticulously
- Gentle tissue handling
a. Every damaged cell placed additional demands on the body’s recovery mechanisms
b. Appropriate location of incisions and adequate incision length - Preserve blood supply to tissues
a. Anatomy is important - Accurate tissue apposition with minimal tension
- Eliminate dead space
○ Dead space predispose to seroma formation and infection
What is important to reduce infections rates during surgery, how does anaesthesia mask bleeding and what does blood do to the operative field
- Surgical lavage reduces infection rates : ‘the solution to pollution is dilution’.
- Bear in mind that anaesthetic agents cause hypotension and hypothermia which both reduce/mask the amount of bleeding
- Blood within the operative field
○ Obscures visualisation
○ Irritates tissue
○ Prevents tissue apposition
○ Delays healing
○ Potentiates infection
Haemostasis via pressure/tamponade and ligation what need to do
- pressure/tamponade -> take 30seconds for a soft clot to form then 2-3 mins for cross-linking of fibrin, guaze swab used to compress and blot
- Ligation - best for secruity, 3 forceps method -> most proximal haemotstat removed and ligature positioned in crushed tissue, then transected between two more distal haemostatic forceps, OR trasnfixing liguature -> placed distal to simple ligature
List 9 reasons you may need to do a exploratory laparotomy
- GI disorders –Foreign bodies / torsion / rupture
- Urogenital abnormalities unresponsive to medical Rx
- Abdominal disorders of unknown origin
- Penetrating trauma
- Acute abdomen
- Generalized peritonitis
- Diagnosis and treatment of portosystemic shunts
- Splenic abnormalities
- Uncontrolled abdominal haemorrhage
When should you do a laparotomy and the 4 main approaches, when to use what
- Patient stabilized OR patient not stabilizing with appropriate supportive therapy
1) ventral midline - most common
2) paracostal - increased exposure of liver
3) flank - ovariohysterectomy/gastropexy
4) retroperitoneal - adrenal neoplasia
What are the 5 main steps in exploratory laparotomy after open abdominal cavity
- Remove Falciform ligament - Aids visualisation
- Suction any peritoneal fluid
- Place Balfour retractors
a. Moistened lap. Sponges
b. Care not to incorporate viscera - Elevate xiphoid to visualize diaphragm, liver and cardia
- Systematic exploration
○ Cranial to caudal, body system -> left to right
○ Colour, texture, shape or viscera / organs
○ Assess movement of gastrointestinal tract
○ Palpate pulses in vessels
Cranial and cranial left quadrant of abdomen what present within
- Diaphragm
- Liver and gall bladder
○ Colour, margin sharpness, focal lesions, texture
○ Gall bladder expressible - Stomach
○ Gastroesophageal sphincter through oesophageal hiatus.
Cranial right quadrant of abdomen what present within
- Duodenum
○ Use meso-duodenum to retract viscera to midline to expose right side of abdomen
○ Anchored by duodenocolic ligament caudally - Pancreas
- Portal vein and caudal vena cava
- Right kidney and adrenal
Caudal left quadrant of abdomen what present within
- Spleen
- Rectum, Colon, Caecum
- Mesenteric root and LN
- Ileum –anti mesenteric vessel
- Jejunum
- Back to duodenum at duodenal colic ligament
- Mesocolon to retract viscera to expose left abdomen to visualize left kidney and adrenal
○ Can see aorta from this position
caudal right quadrant of abdomen what present within
- Bladder and ureters
- Prostate or uterus / ovaries
- Open omental bursa to visualize L limb pancreas
What samples can you take from exploitative laparotomy
Clin path -> culture, sensitivity, cytology, biochemsitry
- swabs or fluid sample
- biopsy -> skin punch biopsy with #11 scapel in GIT, liver, spleen, pancrease
What are the 4steps in laparotomy closure
1) lavage abdomen with warmed 0.9%NaCl - 20-50ml, should be clear
2) external rectus sheath need to incorape into peritoneum
3) close from caudal to cranial direction with continuous appositional suture pattern - synthetic, slow absorbable monofilament
4) SC layers -> 2 layers to decrease dead space -> fast absorption for beneath - subcut
non-absorbale simple interrupted pattern for skin
What are 9 important complications of laparotomy
1. Hypothermia ○ Need active rewarming ○ ideally minimization of heat loss during anaesthesia and surgery ○ Especially in small dogs/cats, young animals 2. Seroma - pocket of serous fluid that can develop within the body after surgery 3. Dehiscence and evisceration 4. Foreign materials left in abdomen ○ Instruments ○ Gauze sponges “gossypiboma” 5. Adhesions ○ Restrictive or non-restrictive 6. Peritonitis 7 Infection 8. Self-trauma –suture knots too tight 9. Skin irritation –clipper reaction
Laparoscopy (keyhole surgery) what occurs and indications for its use
- Minimally invasive alternative to open laparotomy procedure Telescope camera placed intra-abdominally through a trocar. Indications: - Abdominal cryptorchid testes - Ovariectomy / ovariohysterectomy - Liver biopsy - Lap-assisted gastropexy - Lap-assisted cystotomy
What are some clinical consequences of cancer
- Expansile growth
- Destruction of host tissues and function
- Infiltration and metastasis
- Necrosis, ulceration and haemorrhage
- Cachexia - massive body mass loss
- Hormone production - hyperCa
- Reduced quality of life
- Reduced lifespan
What are the 3 main steps in diagnosis of a tumor and what is needed for almost all treatment planning
1. What is it? ○ Neoplastic or non-neoplastic ○ Tumour type/cell of origin? § Round cell, epithelial or mesenchymal 2. How bad is it? ○ Benign or malignant? Grade? 3. Where is it? ○ Clinical staging (spread/extent of cancer) § TNM system A cytologic or histopathologic diagnosis is required in almost all cases
What are the 2 common diagnostic techniques for cancer diagnosis
1. Fine needle aspiration (FNA) for cytology (22g needle) ○ Aspirational vs non-aspirational techniques 2. Surgical biopsy for histopathology ○ Incisional biopsy § Needle core biopsy § Skin punch biopsy § Surgical wedge biopsy § Bone biopsy ○ Excisional biopsy § Removal with margin of normal tissue
What is the difference between aspirational and non-aspirational FNA and which do first
Aspirational - try second
- pull back plunger 1/2 way using negative pressure to aspirate cells and redirect needle 3-5 times then release plunger while still in mass
Non-aspirational - try first
- uses needle only - popping needle in and out, uses capillary action, no suction
describe sample preparation for cytology slides
- Label the glass slide ○ Animal name (first and last) ○ Site § Tissue, organ, location ○ Date - Leave slide to air-dry - Stain with quick stain (if analysis in-house) ○ Tips - use pencil and keep slides away from formalin (alters cell morphology)
What are 7 indications for biopsy
- If FNA cytology non-diagnostic or equivocal
- If type of treatment would be altered
- If extent of treatment would be altered
- Owners willingness to treat would change
- Malignant neoplasia - to grade and plan
- Major or reconstructive surgery is required
- Goal is diagnosis for prognostic purposes
What are important in terms of biopsy tract and scars and what is important with tissue handling
- Biopsy tract must be placed so that it can be removed with definitive surgery
- Biopsy scars or needle tracts are considered contaminated and potentially seeded by neoplastic cells
Handling - Use shape surgery technique
- Avoid electrocautery
- Avoid ulcerated/inflamed tissue
- Handle tissue delicately
- One specimen per container
- thickness: maximum 2cm for formalin
Incisional biopsy when use, what to take and the 4 types with what type of lesions
When complete removal not possible
- Multiple biopsies
- For cores, at least 5mm long
Types
1. Needle biopsy (Bind vs U/S guided) - multiple samples through same skin incision = more tissue = diagnosis
2. skin punch biopsy - percutaneous for superficial lesions
3. surgical wedge - larger piece of tissue can be obtained
4. bone biopsy - advance through the cortex
Excisional biopsy when to use and what does it gain information on
○ Do if surgical dose NOT altered by knowledge of tumour type § Eg - splenectomy for splenic mass ○ Benign tumor based cytology § Lipoma ○ Lymph node § Staging ○ Provides grade information ○ Goal: diagnosis and treatment § Anatomic location allows wide margins
Biopsy submission what are the 4 steps
- Incomplete parallel cuts (1cm apart) can be utilised to assist with appropriate tissue fixation and orientation for large specimens
Want to keep deep margin intact while doing this - label container
- identify marginal - ink, suture ( Single sutures = lateral margins, Two sutures = caudal margins) - NEED TO INFORM PATHOLOGIST ABOUT WHAT YOU CHOOSE
- complete submission form - signalment, history, description, potential diagnosis thoughts
Grading of neoplasm what is the histopathogical criteria and for type of tumor and what does grading information provide
- Pathologists grade tumor’s using histopathological criteria
○ Degree of cellular differentiations (pleomorphism)
○ Number of mitotic figures (growth rate)
○ Degree of necrosis/haemorrhage
○ Evidence of local invasion
○ Presence of metastasis (vascular and lymphatic) - Grading criteria varies with the type of tumour
○ Reports as low vs high grade or numerical grade 1-3 - Grading provides information on the potential behaviour of the tumor
Pathology reports what should you do with it
- Read and interpret the report yourself
○ Always get detailed report, not summary
○ Check that it fits with the clinical picture - What if report does not fit clinical picture
○ Speak with the pathologist (they don’t bite)
○ May perform re-cuts of the biopsy specimen or obtain a second opinion on the FNA or biopsy
What is clinical staging for a neoplasm, what system should is generally used
Knowledge of tumour type, grade and stage dictates surgical dose TNM System developed by WHO T = tumour characteristics § T15 = 15cm diameter tumour N = regional lymph node involvement § N0 = no node enlargement § N1 = regional node enlargement § N2 = next node in chain is enlarged M - metastatic involvement § M0 - no metastases § M1 - metastases present
